Change log

- data is now present for all maps
- added some sanity checking for the WorldMapSize data post processing
- fixed a bug that could cause a Lua error if you passed in one valid map ID and one invalid map ID
- added function: numFloors = Astrolabe:GetNumFloors( mapID )
- changing printError function to a local variable
- fixed TranslateWorldMapPosition() when translating between continents
- treat nil as the first floor of a map when the map HAS floors
- add argcheck calls for :GetMapInfo
- ComputeDistance and TranslateWorldMapPosition now always validate that they at least got a non-nil value for the map id